26 research outputs found
High-accuracy determination of the neutron flux in the new experimental area n_TOF-EAR2 at CERN
A new high flux experimental area has recently become operational at the n_TOF facility at CERN. This new measuring station, n_TOF-EAR2, is placed at the end of a vertical beam line at a distance of approximately 20m from the spallation target. The characterization of the neutron beam, in terms of flux, spatial profile and resolution function, is of crucial importance for the feasibility study and data analysis of all measurements to be performed in the new area. In this paper, the measurement of the neutron flux, performed with different solid-state and gaseous detection systems, and using three neutron-converting reactions considered standard in different energy regions is reported. The results of the various measurements have been combined, yielding an evaluated neutron energy distribution in a wide energy range, from 2meV to 100MeV, with an accuracy ranging from 2%, at low energy, to 6% in the high-energy region. In addition, an absolute normalization of the n_TOF-EAR2 neutron flux has been obtained by means of an activation measurement performed with 197Au foils in the beam.Comisión Europea FP7/2007-2011 No.605203Centro Nacional de Ciencias de Polonia UMO- 2012/04/M/ST2/00700Centro Nacional de Ciencias de Polonia UMO-2016/22/M/ST2/00183Fundación de Ciencia Croata No. 168
A novel co-design approach for soft errors mitigation in embedded systems
Comunicación presentada en the 11th European Conference on Radiation and its Effects on Components and Systems RADECS 2010, Längenfeld, Austria, September 20-24, 2010.A novel proposal to design radiation-tolerant embedded systems combining hardware and software mitigation techniques is presented. Two suites of tools are developed to automatically apply the techniques and to facilitate the trade-offs analyses.This work makes part of RENASER project (ESP2007-65914-C03-03) funded by the 2007 Spain Research National Plan of the Ministry of Science and Education in which context this work has been possible. The work presented here has been carried out thanks to the support of the research project ’Aceleración de algoritmos industriales y de seguridad en entornos críticos mediante hardware’ (GV/2009/098) (Generalitat Valenciana, Spain)
Distributed microprocessor controllers using optic fiber network
This work continues a previous project devoted to the supervision and control of electric motors in large industrial plants. This project consists in a set of microcontroller boards that communicate with a Global Control Card (GCC) The transmission of messages in the system is done using a optic fiber network. The GCC can be linked to a supervisory computer by a serial communication channel. A program processes the system schematics and authomatically generates the configuration files. This project has been realised in collaboration with INABBNSA (ABENGOA) and funded by the ATICA programme
Development of a Tabletop Setup for the Transient Current Technique Using Two-Photon Absorption in Silicon Particle Detectors
The transient current technique (TCT) is widely used in the field of silicon particle detector development. So far, only laser wavelengths with a photon energy larger than or similar to the silicon bandgap (single photon absorption) were used. Recently, measurements using two-photon absorption (TPA) for silicon detector testing have been carried out for the first time. Excess carriers are only created at the focal point of the laser beam and thus resolution in all three spatial directions could be achieved. The resolution perpendicular to the incident laser beam could be increased roughly by a factor of 10. First measurements using this new method were performed at the Singular Laser Facility of Universidad del Pais Vasco (UPV)/Euskal Herriko Unibertzitatea (EHU). Following the initial success of the method, a compact TPA-TCT setup is under development. A first description of the setup and laser system is presented in this articleThis work was supported in part by the Spanish Ministry of Economy and Competitiveness (MINECO) under Grant FPA2013-48387-C6-1-P and in part by the Wolfgang Gentner Programme of the German Federal Ministry of Education and Research under Grant 05E15CH
Measurement of 73Ge(n,γ) cross sections and implications for stellar nucleosynthesis
73Ge(n,γ) cross sections were measured at the neutron time-of-flight facility n_TOF at CERN up to neutron energies of 300 keV, providing for the first time experimental data above 8 keV. Results indicate that the stellar cross section at kT=30 keV is 1.5 to 1.7 times higher than most theoretical predictions. The new cross sections result in a substantial decrease of 73Ge produced in stars, which would explain the low isotopic abundance of 73Ge in the solar system.Fondo de Ciencia de Austria J3503Consejo de Instalaciones de Ciencia y Tecnología Reino Unido ST / M006085 / 1Consejo Europeo de Investigación ERC-2015-StG Nr.677497
The new vertical neutron beam line at the CERN n_TOF facility design and outlook on the performance
At the neutron time-of-flight facility n_TOF at CERN a new vertical beam line was constructed in 2014, in order to extend the experimental possibilities at this facility to an even wider range of challenging cross-section measurements of interest in astrophysics, nuclear technology and medical physics. The design of the beam line and the experimental hall was based on FLUKA Monte Carlo simulations, aiming at maximizing the neutron flux, reducing the beam halo and minimizing the background from neutrons interacting with the collimator or back-scattered in the beam dump.
The present paper gives an overview on the design of the beam line and the relevant elements and provides an outlook on the expected performance regarding the neutron beam intensity, shape and energy resolution, as well as the neutron and photon backgrounds
Investigation of the 240Pu(n, f ) reaction at the n_TOF/EAR2 facility in the 9 meV–6 MeV range
Background: Nuclear waste management is considered amongst the major challenges in the field of nuclear energy. A possible means of addressing this issue is waste transmutation in advanced nuclear systems, whose operation requires a fast neutron spectrum. In this regard, the accurate knowledge of neutron-induced reaction cross sections of several (minor) actinide isotopes is essential for design optimization and improvement of safety margins of such systems. One such case is
240
Pu
, due to its accumulation in spent nuclear fuel of thermal reactors and its usage in fast reactor fuel. The measurement of the
240
Pu
(
n
,
f
)
cross section was previously attempted at the CERN n_TOF facility EAR1 measuring station using the time-of-flight technique. Due to the low amount of available material and the given flux at EAR1, the measurement had to last several months to achieve a sufficient statistical accuracy. This long duration led to detector deterioration due to the prolonged exposure to the high
α
activity of the fission foils, therefore the measurement could not be successfully completed.
Purpose: It is aimed to determine whether it is feasible to study neutron-induced fission at n_TOF/EAR2 and provide data on the
240
Pu
(
n
,
f
)
reaction in energy regions requested for applications.
Methods: The study of the
240
Pu
(
n
,
f
)
reaction was made at a new experimental area (EAR2) with a shorter flight path which delivered on average 30 times higher flux at fast neutron energies. This enabled the measurement to be performed much faster, thus limiting the exposure of the detectors to the intrinsic activity of the fission foils. The experimental setup was based on microbulk Micromegas detectors and the time-of-flight data were analyzed with an optimized pulse-shape analysis algorithm. Special attention was dedicated to the estimation of the non-negligible counting loss corrections with the development of a new methodology, and other corrections were estimated via Monte Carlo simulations of the experimental setup.
Results: This new measurement of the
240
Pu
(
n
,
f
)
cross section yielded data from
9
meV
up to
6
MeV
incident neutron energy and fission resonance kernels were extracted up to
10
keV
.
Conclusions: Neutron-induced fission of high activity samples can be successfully studied at the n_TOF/EAR2 facility at CERN covering a wide range of neutron energies, from thermal to a few MeV.Croatian Science Foundation 857
Guía docente común de las titulaciones de Ingeniero en Electrónica en las universidades andaluzas
El presente documento constituye el resultado del trabajo elaborado de acuerdo con la Convocatoria de Elaboración de Guías Docentes de Titulaciones Andaluzas conforme al Sistema de Créditos Europeos (años 2005/2006) de la Dirección General de Universidades, dependiente de la Secretaría General de Universidades, Investigación y Tecnología de la Consejería de Innovación, Ciencia y Empresa de la Junta de Andalucía
Detector predictivo de faltas en maquinas rotativas
Detector predictivo de faltas en máquinas eléctricas rotativas.El sistema objeto de la presente invención permite conocer el estado de salud de una máquina eléctrica en tiempo real, mediante la medida de la corriente de estator y la detección de deterior
Application-driven co-design of fault-tolerant industrial systems
This paper presents a novel methodology for the HW/SW co-design of fault tolerant embedded systems that pursues the mitigation of radiation-induced upset events (which are a class of Single Event Effects - SEEs) on critical industrial applications. The proposal combines the flexibility and low cost of Software Implemented Hardware Fault Tolerance (SIHFT) techniques with the high reliability of selective hardware replication. The co-design flow is supported by a hardening platform that comprises an automatic software hardening environment and
a hardware tool able to emulate Single Event Upsets (SEUs). As a case study, we selected a soft-micro (PicoBlaze) widely used in FPGA-based industrial systems, and a fault tolerant version of the matrix multiplication algorithm was developed. Using the proposed methodology, the design was guided by the requirements of the application, leading us to explore several trade-offs among reliability, performance and cost.This work makes part of RENASER project (ESP2007-65914-C03-03) funded by the 2007 Research National Plan of the Ministry of Science and Education in which context this work has been possible. The work presented here has been carried out thanks to the support of the research projects ’Aceleración de algoritmos industriales y de seguridad en entornos críticos mediante hardware’ (GV/2009/098) (Generalitat Valenciana) and ’Aceleración hardware de algoritmos industriales para el sector calzado’ (GRE08-P11) (University of Alicante)